A controlled trial of castration with and without nilutamide in metastatic prostatic carcinoma.

A randomized double-blind trial in patients with disseminated, previously untreated prostate cancer (Stage D2) was conducted in eight Canadian centers. All 203 patients enrolled in this study underwent bilateral orchiectomy and were randomized to receive either the nonsteroidal anti-androgen nilutamide or a placebo. Patient responses were graded according to the criteria of the National Prostatic Cancer Project (NPCP). Patients treated with nilutamide had a significantly greater number of positive objective responses (partial and complete regression) than did the patients treated with castration alone (46% versus 20%, P = 0.001). Progression-free survival was improved initially in the nilutamide group, but the median time to progression was 12 months for both groups. Despite an increase in the median length of survival from 18.9 to 24.3 months with the nilutamide, the survival time was not significantly longer in the nilutamide group (log = rank test, P = 0.048). Although minor side effects were frequent, adverse effects related to the medication and leading to discontinuation of treatment were observed in 9% of cases. These results suggest some benefit of the combined treatment (orchiectomy + nilutamide) over orchiectomy alone in the treatment of metastatic prostatic carcinoma.